Application of logs
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The number of milligrams, $d$, of a drug remaining in a patient's bloodstream, $t$ hours after it has been administered, is given by the equation $d = 5(2.7^{.04t})$. To the nearest minute, how long will it take until only $2.5$ mg of the drug remains in the system?
First, I set the equation equal to 2.5 and solved for $t$, where $t=1.7$. However, I am way off from my teacher's answer which was 31 hours and 45 minutes. I'm uncertain of another way to solve the problem. What else do I need to do?
logarithms applications
edited Jan 24 at 3:49
Gnumbertester
670114
asked Jan 24 at 3:17
BibliophileBibliophile
818
$endgroup$
add a comment |
$begingroup$
The number of milligrams, $d$, of a drug remaining in a patient's bloodstream, $t$ hours after it has been administered, is given by the equation $d = 5(2.7^{.04t})$. To the nearest minute, how long will it take until only $2.5$ mg of the drug remains in the system?
First, I set the equation equal to 2.5 and solved for $t$, where $t=1.7$. However, I am way off from my teacher's answer which was 31 hours and 45 minutes. I'm uncertain of another way to solve the problem. What else do I need to do?
logarithms applications
edited Jan 24 at 3:49
Gnumbertester
670114
asked Jan 24 at 3:17
BibliophileBibliophile
818
$endgroup$
3
$begingroup$
I think the tag algebraic-topology should be removed
$endgroup$
– Aditya Dua
Jan 24 at 3:23
$begingroup$
Use MathJax for typesetting. It is not possible to read the equation describing the evolution of $d(t)$ as currently posted.
$endgroup$
– Aditya Dua
Jan 24 at 3:24
1
$begingroup$
The equation that you gave grows over time, are you sure that you have posted it correctly?
$endgroup$
– Gnumbertester
Jan 24 at 3:29
add a comment |
$begingroup$
The number of milligrams, $d$, of a drug remaining in a patient's bloodstream, $t$ hours after it has been administered, is given by the equation $d = 5(2.7^{.04t})$. To the nearest minute, how long will it take until only $2.5$ mg of the drug remains in the system?
First, I set the equation equal to 2.5 and solved for $t$, where $t=1.7$. However, I am way off from my teacher's answer which was 31 hours and 45 minutes. I'm uncertain of another way to solve the problem. What else do I need to do?
logarithms applications
edited Jan 24 at 3:49
Gnumbertester
670114
asked Jan 24 at 3:17
BibliophileBibliophile
818
$endgroup$
The number of milligrams, $d$, of a drug remaining in a patient's bloodstream, $t$ hours after it has been administered, is given by the equation $d = 5(2.7^{.04t})$. To the nearest minute, how long will it take until only $2.5$ mg of the drug remains in the system?
First, I set the equation equal to 2.5 and solved for $t$, where $t=1.7$. However, I am way off from my teacher's answer which was 31 hours and 45 minutes. I'm uncertain of another way to solve the problem. What else do I need to do?
logarithms applications
logarithms applications
edited Jan 24 at 3:49
Gnumbertester
670114
asked Jan 24 at 3:17
BibliophileBibliophile
818
edited Jan 24 at 3:49
Gnumbertester
670114
asked Jan 24 at 3:17
BibliophileBibliophile
818
edited Jan 24 at 3:49
Gnumbertester
670114
edited Jan 24 at 3:49
Gnumbertester
670114
edited Jan 24 at 3:49
Gnumbertester
670114
670114
asked Jan 24 at 3:17
BibliophileBibliophile
818
asked Jan 24 at 3:17
BibliophileBibliophile
818
asked Jan 24 at 3:17
BibliophileBibliophile
818
818
3
$begingroup$
I think the tag algebraic-topology should be removed
$endgroup$
– Aditya Dua
Jan 24 at 3:23
$begingroup$
Use MathJax for typesetting. It is not possible to read the equation describing the evolution of $d(t)$ as currently posted.
$endgroup$
– Aditya Dua
Jan 24 at 3:24
1
$begingroup$
The equation that you gave grows over time, are you sure that you have posted it correctly?
$endgroup$
– Gnumbertester
Jan 24 at 3:29
add a comment |
3
$begingroup$
I think the tag algebraic-topology should be removed
$endgroup$
– Aditya Dua
Jan 24 at 3:23
$begingroup$
Use MathJax for typesetting. It is not possible to read the equation describing the evolution of $d(t)$ as currently posted.
$endgroup$
– Aditya Dua
Jan 24 at 3:24
1
$begingroup$
The equation that you gave grows over time, are you sure that you have posted it correctly?
$endgroup$
– Gnumbertester
Jan 24 at 3:29
3
3
$begingroup$
I think the tag algebraic-topology should be removed
$endgroup$
– Aditya Dua
Jan 24 at 3:23
$begingroup$
I think the tag algebraic-topology should be removed
$endgroup$
– Aditya Dua
Jan 24 at 3:23
$begingroup$
Use MathJax for typesetting. It is not possible to read the equation describing the evolution of $d(t)$ as currently posted.
$endgroup$
– Aditya Dua
Jan 24 at 3:24
$begingroup$
Use MathJax for typesetting. It is not possible to read the equation describing the evolution of $d(t)$ as currently posted.
$endgroup$
– Aditya Dua
Jan 24 at 3:24
1
1
$begingroup$
The equation that you gave grows over time, are you sure that you have posted it correctly?
$endgroup$
– Gnumbertester
Jan 24 at 3:29
$begingroup$
The equation that you gave grows over time, are you sure that you have posted it correctly?
$endgroup$
– Gnumbertester
Jan 24 at 3:29
add a comment |
1 Answer
1
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oldest
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$begingroup$
d = 5*(2.7^.04t) //(original equation)
2.5 = 5*(2.7^.04t) //(set equation equal to 2.5)
0.5 = 2.7^.04t //(divide by 5 on both sides)
log base 2.7 of 0.5 = 0.04t //(log function)
t = 17.446241... //(Answer)
You should probably talk to your teacher and ask her how he/she did the question.
answered Jan 28 at 4:04
DhanushDhanush
212
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add a comment |
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$begingroup$
d = 5*(2.7^.04t) //(original equation)
2.5 = 5*(2.7^.04t) //(set equation equal to 2.5)
0.5 = 2.7^.04t //(divide by 5 on both sides)
log base 2.7 of 0.5 = 0.04t //(log function)
t = 17.446241... //(Answer)
You should probably talk to your teacher and ask her how he/she did the question.
answered Jan 28 at 4:04
DhanushDhanush
212
$endgroup$
add a comment |
$begingroup$
d = 5*(2.7^.04t) //(original equation)
2.5 = 5*(2.7^.04t) //(set equation equal to 2.5)
0.5 = 2.7^.04t //(divide by 5 on both sides)
log base 2.7 of 0.5 = 0.04t //(log function)
t = 17.446241... //(Answer)
You should probably talk to your teacher and ask her how he/she did the question.
answered Jan 28 at 4:04
DhanushDhanush
212
$endgroup$
add a comment |
$begingroup$
d = 5*(2.7^.04t) //(original equation)
2.5 = 5*(2.7^.04t) //(set equation equal to 2.5)
0.5 = 2.7^.04t //(divide by 5 on both sides)
log base 2.7 of 0.5 = 0.04t //(log function)
t = 17.446241... //(Answer)
You should probably talk to your teacher and ask her how he/she did the question.
answered Jan 28 at 4:04
DhanushDhanush
212
$endgroup$
d = 5*(2.7^.04t) //(original equation)
2.5 = 5*(2.7^.04t) //(set equation equal to 2.5)
0.5 = 2.7^.04t //(divide by 5 on both sides)
log base 2.7 of 0.5 = 0.04t //(log function)
t = 17.446241... //(Answer)
You should probably talk to your teacher and ask her how he/she did the question.
answered Jan 28 at 4:04
DhanushDhanush
212
answered Jan 28 at 4:04
DhanushDhanush
212
answered Jan 28 at 4:04
DhanushDhanush
212
answered Jan 28 at 4:04
DhanushDhanush
212
212
add a comment |
add a comment |
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3
$begingroup$
I think the tag algebraic-topology should be removed
$endgroup$
– Aditya Dua
Jan 24 at 3:23
$begingroup$
Use MathJax for typesetting. It is not possible to read the equation describing the evolution of $d(t)$ as currently posted.
$endgroup$
– Aditya Dua
Jan 24 at 3:24
1
$begingroup$
The equation that you gave grows over time, are you sure that you have posted it correctly?
$endgroup$
– Gnumbertester
Jan 24 at 3:29